Tape drives may be used to store computer data or information. In many tape drives, the information or data is stored on the tape in “tracks.” Tracks generally extend linearly along the length of the tape. A head assembly positioned near the tape typically writes to or reads from the tracks on the tape. As used herein, “accessing” information on a tape refers inclusively to reading or writing information on a tape. As the tape is transported across the head assembly, the information can be accessed as desired.
With the increasing reliance on computerization in all aspects of our lives, there is an increasing need for additional storage capacity. Accordingly, new generations of tape drives have increased storage capacity. In part, this increased capacity has been accomplished by using increasingly smaller track spacing between the tracks. As the track spacing decreases, the tape drive's tolerance for misalignment of the tape with respect to the head assembly of the tape drive also decreases. Accordingly, a smaller misalignment can actually cause accessing (reading from or writing to) an improper track on the tape.
Misalignment of the tape with the head assembly can be caused by tape tilt. Tape tilt may be characterized by the tape moving across the head assembly at an angle relative to the head assembly. Physical tolerances in the tape or the tape drive often cause tape tilt. For example, guide rollers in the tape drive are generally used to guide the tape across the head assembly. If these guide rollers are even slightly larger than the width of the tape, the tape may become angled just by changing position within the guide rollers. Accordingly, tape tilt can change while accessing the tape.